Add me to the list of folks experiencing this trouble.  Using the H3000 2.5.1 AU with Digital Performer 8.07 on a Macbook Pro with OS X 10.10.3.  Haven't tried the VST.

Patches take better part of a minute to load and interface seems a bit sluggish adjust just the Mix% parameter while a  project is playing.  Other plugs working just fine.  Audio out of the H3000 otherwise works and sounds great.

Best,

Chuck